Here are some of the oddballs ones I've run into. A customer on v2016 Adv using Bit Defender AV had set their exclusions but it was still slow and it turned out IT had applied the AV policy to server only, instead of both server and workstations. Although they were on Adv Crystal forms still printed slowly (since they run client side unless CS ODBC driver is enabled). On Standard, everything would have been slow. Maybe Sophos is like Bit Defender too?? I imagine some others here would know.
Also, recently a customer on v2019 had slow performance with WebRoot despite all the AV exclusions set. It turns out another AV was running at the same time. On the server, Windows Defender Antivirus (not to be confused with Windows Defender Firewall) which has been renamed to Microsoft Defender btw, which is built into the server o/s, was setup to do realtime monitoring. Disabling that fixed it. Hope that helps.
------------------------------
Alnoor Cassim
Email:
alnoor@asifocus.comPh: 949-689-9887
Orange County, CA
------------------------------